After tripping over my Stainless Works long tubes in the garage I thought I would ask this question. Just how truly restrictive is the stock exhaust on the 07-14 GT500's? The most identified part of the exhaust system to be restrictive are the exhaust manifolds. Although they look restrictive Ford used the same manifolds on all the GT500's from 07 to 14. Whipple and KB make smog legal 750 motor HP all day long with no problem. In fact I believe I read KB making upwards of 850HP thru the factory manifolds and cats. Shelby used the stock exhaust with the Super Snakes except for mufflers. I am not trying to down play the benefits of long tubes with big blower, big boost, big HP applications making the most use of blower volume and boost. We have all read about the big gains of adding headers and the required tune. Are the gains created more from the tune than the headers? Articles show minimal gains from just headers alone but add the tune and then your making nice gains. These are just questions for a January day. Thanks to all on this great forum.
Another exhausting exhaust question
- Thread starter Harry08
- Start date
Part of the equation is forced induction (boost, supercharger etc). A naturally aspirated car has less than 100% volumetric efficiency, so it relies on piston vacuum and exhuast expansion to get air in and exhaust out, with scavenging of the intake and exhaust strokes critical to making power. Intake runners and exhaust runners need to be optimized to see good numbers and thus an intake manifold and header upgrade has more positive effect.
Since our cars make their power with forced induction, our engines EXCEED 100% volumetric efficiency. Meaning we force more air in and force exhaust out than the engine mechanical can do on their own through piston vacuum. Because our cars have pressurized air being forced into the cylinder, our engines are far less reliant on scavenging and "optimized" flow. EVERY little bit helps, but the gains arent as significant.
Until you start moving stupid amounts of air in and have a massive amount of exhaust to get out, the factory logs are good enough. Certainly though, youll see a benefit adding long tubes, but its not as significant a gain under 800-1000 crank HP/torque on our cars as a naturally aspirated car would see.
Since our cars make their power with forced induction, our engines EXCEED 100% volumetric efficiency. Meaning we force more air in and force exhaust out than the engine mechanical can do on their own through piston vacuum. Because our cars have pressurized air being forced into the cylinder, our engines are far less reliant on scavenging and "optimized" flow. EVERY little bit helps, but the gains arent as significant.
Until you start moving stupid amounts of air in and have a massive amount of exhaust to get out, the factory logs are good enough. Certainly though, youll see a benefit adding long tubes, but its not as significant a gain under 800-1000 crank HP/torque on our cars as a naturally aspirated car would see.
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Great information. Thank you.
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